Air Bag System Not Airing Back Up After Retracting Jacks

[tzimmermn]

I have a 2007 Winnebago Tour 40FD on a Freighliner Chassis. I am experiencing a problem with the air bags not filling back up for travel mode after retracting the the jacks (store mode) and starting up the engine. The air pressure on the gauges is fine. It has done this the last 2 times out and I have to manually cycle the air valve on the front cross member by depressing one of the little pins on the block to fill the air backs per Freighliner instructions to get me going. The bags deflate normally when pushing the auto level button. However, they do not pressurize and restore to the travel mode when the engine is started and idled before travel.

What are the logically things to check to trouble shoot this problem and determine whether it is the valve block, wiring, or the signal to shuttle the valve back to the travel mode. Also, where does this restore signal come from or is it a default condition. I am a Mechanical Engineer and have excellent troubleshooting skills, but usually need a starting point such as a schematic or a description that describes how the system is connected and what makes it work. I can speculate how the system is probably designed and built, but that does not always work when I do not have a starting point. I have tools and electrical test equipment to do trouble shooting as may be required.

Any help is appreciated.

Thank you in advance.

Terry

[dickandlois]

Hi Terry!

Wish they made all the systems the same,but not the case.

The best help I can give. There is an Air Suspension Manifold Mod. with three 1/4in. air lines that supply air to the air bags. yellow is the color listed in my information,but it could be a different color, there will be 3 of them and they will be the same color coming from the manifold. one for each front air bag and a single one for the back two air bags.

The forth line is white that air supply's line air to the manifold. It comes from the dump valve that drops the ride pressure. Down goes the coach. When one portion of the valve is powered by 12 volts. The other 12 volt feed, powers the jacks up section of the valve and allows air to go to the air ride bags, up goes the coach.

The dump control valve is its name and job. (so you need 12 volts for up and 12 volts for down at the dump valve, going to 2 different points on the dump valve) Check for a good 12 volts and a good ground !!!

Now the trick is to find the valve,not a clue where it would be in your case. Need to fallow that one odd colored line from the suspension manifold Mod.

Must admit that My thought would be to look for the dump valve up near the front, because the supply air line is connected through one side of the park air brake switch, the one you pull out when parked.

That supply line is also 1/4in. and is black in my information. Looks like the line colors change at the dump valve. Black input to White output to the manifold for air ride system.

When you do your manual thing it may be close the the dump valve ?

Hope that helps. Rich.

Work safe its tight under there when the ride is up and even less when its down.

[Guest Wayne77590]

2008 Winni - That is what has happened to me twice. Once in the first week of ownership, and about a month ago taking it out of storage. In both instances I extended the jacks as far as I could and then retracted them. That cleared up the situation both times.

So far, knock on wood. I'll be following this thread.

[tzimmermn]

Thanks a bunch for the info. I will trace back and see if I can find what is not restoring the air to the air bags. Once in the travel mode it airs up each time after setting, but when I park and cycle the auto level and then the restore, it does not cycle the valve back to the travel mode and leaves bags deflated. There are 3 air lines down there that I recall. It could be a ground as postulated. It quit restoring after I was returning from a trip from California last December 23 and had to go through blizzard, driving rain, 50 mph cross-winds almost the whole trip through AZ, and NM. I am surprised anything works. I am still cleaning out sand and road cinder from the toad where they applied sand to the roads. I will crawl back under and see what I can find.

I appreciate the response and let you know what I find out if anything as to cause.

[dickandlois]

Terry,

Just one more item to check. Have you pulled the bled off lanyards for the primary and secondary air tanks on a regular bases? Water in the system can mess up the valves and cause a number if air issues.

The air drier filters should be changed on a regular bases. They can start to fail and sneak up on you.

Rich.

[tzimmermn]

Thanks Rich. I will check those also. I have been pulling them regualarly (once every 6 mo.) to check for moisture, but they seem to only vent dry air. We live in a dry area with minimal humidity so I would not expect to see too much water collecting in the tanks. I have not noticed anything unusual in this area.

Terry

[PhilipNotz]

My rear air bags did not air up for me after I jack-up our Class-A Gulfstream too high using wooden blocks so the back tires were a couple inches off the ground. Underneath the rig between the wheels, there is a rod with an elbow (shaped like an "L") coming-off the driver's side airbag and going to a controller. Apparently this rod helps the air bag controller mechanically know how high up or down the aisle is extended or tracked from the chassis.

In our case, the RV had been jack-up so high (on wooden blocks so the wheels were off the ground) to get it leveled, the normal shape of the "L" rod had gone to a straight line (or "I"). When we let the jacks down the rod reversed itself to a "backwards L". The "on-shoulder of the highway" solution was to jack the RV back-up on blocks until the rod was straight and use a broom stick to guide the rod to go back into its normal position. Watch out, the air bags with "Suddenly" inflate with a "loud pop". We have never jacked the RV up the high again.

I hope this help you.

[wolfe10]

Phillip,

Welcome to the FMCA Forum.

Yes, there IS a learning curve for RV'ing.

Actually, you are VERY lucky. The rear wheels are your parking/emergency brake. Lifting them off the ground, particularly on sloping ground makes it very likely the rig could surge downhill! NEVER raise the rear wheels of any RV off the ground.

And the rod you are talking about controls RIDE HEIGHT, linking the axle to the RIDE HEIGHT VALVE which is mounted on the chassis. Ride height is VERY important and needs to be checked and set to your chassis maker's specs. You can damage the drive shift, transmission and/or suspension components by having ride height out of spec. Just consider the big change in angle on that 18" long DP drive shift if you are even just 1" out of spec.

Brett

[tzimmermn]

I have finally got around to investigating this problem. In reviewing the HTH control circuit board that controls the leveling, I discovered that it has a multitude of fuses mounted on the board. One is identified as "travel mode". It is a 5 amp mini fuse. It was blown. I have replaced and have had no problem. This appears to be one of those mystery events where I could not find cause for blown fuse. The HTH control panel is visible through a plexiglass window and mounted to the front of the hydraulic solenoid compartment below the passenger side step on the chassis frame. With the front hood open the control panel is visible to the left of generator. This fuse and relay circuit resets the air bag fill shuttle valve back to normal travel mode. I appreciate all the replies as they provided great leads. The forum is very informative to do it yourself owners I learn something new each day.

Again thanks everyone.

[tbutler]

Thanks tzimmermn,

Your report on the solution to your problem helps everyone following this discussion to know what the problem was and how you solved it. Too often the originator of the discussion never returns with a report like yours. This makes the whole discussion much more valuable to everyone. I hope others will follow your example.

[tzimmermn]

Appreciate the kind words Mr Butler and hope the solution helps someone else. Owning an RV is like owning a house and vehicle all in one. Lots of opportunities for issues to crop up. Half the battle is figuring out how the systems are put together. I have been forunate in having a managable amount of issues to deal with thus far. Each time I solve a problem, I learn a little more about my coach. Hope to spend more time with our coach when I finally retire and can enjoy more.

Again Thanks.

Terry Zimmerman

[snowbear]

I trying to help a friend with a 2004 Winnebago Vectra on a Evolution Freightliner chassis. He can not put out any slides or fill his airbags or get his jacks down. We replaced a 5A fuse in the HWH panel. This has happened before. Any help would be appreciated.

Gary

[dickandlois]

Merry Christmas Gary, and welcome.

Could you list the Model HWH system on the coach along with the control panel part number.

Then the posters on the forum can better pin down the problem.

Now to finish playing Santa and some rest.

Rich.

[snowbear]

Rich, sorry for the late reply. It is a model 325 and he can not find a p/n for the control panel. The fuse that was replaced was found in a box found down on the lower right in front of the steps. It seems like it would be a 12V problem that ties the the HWH system and airbags together. Something that is common to both. I hope your readers are able to help. He does not use a computer so if someone that is sharp on this may have to call him. Let me know and I'll get his ph # for them or have him call them.

Thanks,

Gary

[dickandlois]

Gary, I sent you some information in a (PM) Private Message that should show up in your personal email. I hope that it helps in your quest for a solution to the problem.

Keep me in the loop and pass along your findings. This information leads to a sight that covers the HWH system that might be real close to the system your working on.

Rich.

[snowbear]

Rich, thanks, it does look promising. I'll let you know how it works out.

G.